do not access vector elements beyond size, rhbz#847519 related
do not access vector elements beyond size, rhbz#847519 related

The actual bug (crash) is not triggered anymore because the categories
are assembled differently, nevertheless the code in question could
expose the same behavior under different preconditions.

Change-Id: Ic37f6b34effaf4e5252e80aab46b021547b36efb

JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core